Matrix metalloproteinases are naturally occurring enzymes found in most mammals and are associated with the breakdown of connective tissues. The class includes gelatinase A and B, stromelysin-1, fibroblast collagenase, neutrophil collagenase, matrilysin, and other forms of collagenase. These enzymes have been implicated with a number of diseases which result from breakdown of connective tissue, such as rheumatoid arthritis, osteoarthritis, osteoporosis, periodontitis, multiple sclerosis, gingivitis, corneal epidermal and gastric ulceration, atherosclerosis, neointimal proliferation which leads to restenosis and ischemic heart failure, and tumor metastasis. A method for preventing and treating these diseases is now recognized to be by inhibiting metalloproteinase enzymes, thereby curtailing and eliminating the breakdown of connective tissues that results in the disease states.
Several inhibitors of metalloproteinases have been identified. Many inhibitors are complex peptides, for instance as described by Chapman, et al., in J. Med. Chem., 1993;36:4293-4301. Small peptide inhibitors are also known, for example as described in U.S. Pat. Nos. 4,599,361 and 5,270,326, as well as nonpeptides as in WO 95/35276.
The need continues for small molecular weight molecules which can be economically prepared and yet are effective inhibitors of metalloproteinases. We have now discovered a group of butyric acid derivatives which have exceptionally good inhibitory activity. An object of this invention is to provide such compounds, their pharmaceutical formulations, and a method for using them to treat diseases mediated by metalloproteinases.